2.2 the focus and aim of landuse
change and urban growing
monitoring
The focus of landuse change and urban
growing monitoring is to monitor the
occupy of the agriculture land. In China,
the important monitoring objects will
include all provincial capitals, developed
cities in the eastern and others important
cities. In these cities, zones between the
urban and rural, important economic
development zones and commercial
zones, the sides of important country
roads, the large and middle construction
objects licensed by government will be
the focus in the monitoring.
RS monitoring is the means with high
speed, accurate and efficiency, it not
only gives the amount and location of
the change information of landuse, but
also can be used to check the data
supplied by local government. It gives
the administrators with scientific
assistance in the macro managing,
planning and utilizing the land resource.
It is also an important means in
constructing the system of national
landuse dynamic monitoring.
3. technical route and key technique
of landuse change and urban
growing monitoring
The data sources for landuse change and
urban growing monitoring including the
SPOT pan&multi-spectrum data, TM
multi-spectrum data, IRS-1C data, SAR
data and other high resolution RS data.
Monitoring Zone are often used in the
works of landuse change and urban
growing monitoring. The choice of
suitable monitoring zone not only helps
to reduce work amount, but also
improve the precise of change
information. The county administrative
area is often used as the monitoring
zone.
In order to keep consistent with the
means and data of existing country
landuse investigation, A classification
system of RS monitoring are made refer
to the classification system of country
landuse status investigation. It including:
Agriculture land: cultivated land, forest,
garden, grassland, river, lake, reservoir
and pool, etc;
Construct land: residence, industry,
mineral land, transport land, gorge and
channel, buildings over the water;
Unutilized land: Unutilized land,
beachhead, reed land, iceberg,
permanent snow;
uncultivated land: the land without
plants temporary;
Unused Construct land;
This classification system is the basis to
interpret and classify the RS data. The
common methods of classification
include interpretation with eyes,
supervise classifying, unsupervise
classifying and others.
The technique route of RS monitoring
will be introduced in the context, which
is drawn up from experiments.
3.1 image geometric proceeding
Image geometric proceeding is to
proceed multi-sources data with such
steps as the choice of control point,
image rectification, image mosaic and
image tone adjust, etc. In the end, multi-sources
data will be integrated to the
same coordinate system and the same
image resolution, prepared for the image
merging, image cover and change
information extraction.
The control point materials can be the
control points from fieldwork, or
densification points, or points directly
got from the map. The means of point
choice can be the image referring to the
map, or the image referring to the image.
The models of rectification include
geometric polynomial rectification, or
digital differential rectification.
Geometric polynomial rectification suits
for the terrain, and digital differential
rectification for hills and mountains or
the SPOT data with large inclination
angle.
3.2 image merging
RS data qualified with the characters of
multi-spectrums, multi-spatial
resolutions and multi-sensors. In order
to utilize the advantages of these multi-sources
RS data, merging technique is
used to acquire the high resolution of
SPOT data (or similar data) and the
multi-spectrum of TM data (or similar
data). The merging data have higher
interpreting precise. Before merging,
what must be done is to improve the
characters of each image separately. The
color spatial transform (IHS), K.L.
transform and wave let transform are the
normal merging methods.
3.3 extract of change information
Change information refers to the change
of feature object in the location, range
and types during a period. It can be
classified to several types according to
“the rule of landuse dynamic remote
sensing monitoring”:
New urban, rural residence, isolate
industry and mineral building occupy
the cultivated land ;
New urban, rural residence, isolate
industry and mineral building occupy
the non-cultivated land;
New railways, roads, airports and other
building occupy the cultivated land;
New railways, roads, airports and other
building occupy the non-cultivated land ;
The cultivated land transferred into
water and other non-construct land ;
New cultivated land;
Uncultivated land ;
Unused Construct land;
The means of extracting change
information from image include the
subtract of image, Principal Components
Analysis, the subtract of vegetation
index, classification comparing, the
comparing between classification results
and maps, etc.
